#top{
    width: 780px;
    height: 183px;
    background-color: darkgreen;
    margin-bottom: 2px;
}
#nav{
    background:url(../img/banner.jpg);
    width: 780px;
    height: 150px;
    text-align: center;
}
#car li{
    float: left;
    width: 78px;
    background:url(../img/button1.jpg);
    height: 33px;
    text-align: center;
    line-height: 33px;
}
#car a:hover{
    position: relative;
    bottom: 1px;
    right: 1px;
    background: url(../img/button1_bg.jpg)no-repeat;
    display: block;

}

